Fuel-feeding device of internal-combustion engines



l 624 024 April 12 1927' o. SVENSSON ET AL FUEL FEEDING DEVICE OFINTERNAL COMBUSTION ENGINES Filed March 17 1923 5 f $7M, n we w ATree/vex? Patented Apr. 12, 1927.

* UNITED STATES PATENT OFFICE.

OSKAR SVENSSON AND GUSTAF SVENSSON, OF DAGLOSEN, SWEDEN.

FUEL-FEEDING- DEVICE OF INTERNAL-COMBUSTION ENGINES.

Application filed March 17, 1923, Serial No. 625,815, and in GermanyApril 18, 1922.

This invention relates to a fuel feeding device for internal combustionengines of the two stroke cycle system. As in engines of a constructionbefore known the fuel inlet is provided in the channel extending fromthe crank chamber to the working cylinder. According to the invention apart of the said channel has great width and slight height, the fuelinlet being located at the said part, so that the fuel, sucked into thechannel by the vacuum in the crank chamber, is spread on a comparativelygreat surface of the wall of the channel and the air, when afterwardspassing from the crank chamber into the cylinder, carries with itselfthe fuel, thus spread, and divides the same, the fuel and air being thusmingled and constituting an explosive charge. At the said part of thechannel, preferably, a throttle member is provided, slanting toward thesaid fuel inlet and the mouth of the channel, the said member causingthe air, leaving the crank chamber, to strike the fuel spread on thewall of the channel, so that the air more forcibly carries with itselfthe fuel and divides the same.

Fig. 1 shows in vertical cross section an internal combustion engine ofthe two stroke cycle system arranged in accordance with this invention.

Fig. 2 is a fragmentary cross-section taken on the line 22 of Fig. 1.

The piston 1 compresses during its downward stroke in the workingcylinder 2 in the ordinary manner the air which during the previousupward stroke of the piston has been sucked into the crank chamber 3 andthe lower part of the cylinder 2 through the valve 4. 5 is the channelextending from the crank chamber 3 and put into communication with theworking cylinder, as the piston 1, at the end of its downward strokeuncovers the mouth 6. According to the invention a part of the channel5, preferably the part located immediately before the mouth 6 anddesignated by 7, is so arranged, that the air compressed in the crankchamber will divide the fuel and be mingled with the same while rushingthrough the channel. Preferably, the part 7 of the channel ishorizontal, the cross section of the same being rectangular, so that thepart 7 has a slight height and a great width. By this structure a mixingchamber having a large horizontal diffusion surface is provided, overwhich the fuel may spread while the air is brought into close contacttherewith. In the bottom wall of the channel one or more inlets or mouthpieces for liquid fuel are provided, the said fuel being suppliedthrough a pipe 8, extending, for instance, from a float chamber 9. Inthe pipe 8 a return pressure valve 10, for instance a ball valve, isprovided. In the engine shown in the drawing the part 7 of the channelis provided with a throttle valve 11, located, preferably, immediatelybefore the fuel inlet and consisting of a disk, which is swingably fixedto the top wall of the channel and may be shifted by the operator into aslanting position toward the mouth of the channel.

The engine operates in the following manner. During the partialvacuumcreated in the crank chamber during the upward stroke of the piston 1,fuel passes into the part 7 of the channel 5 and isspread on the wall ofthe channel. At the end of the subsequent downward stroke of the pistonthe mouth 6 of the channel is suddenly uncovered by the piston, whichresults in the air compressed in the crank chamber rushin through thechannel 5 and the portion 7, and

into the working cylinder carrying with it-' self the fuel, which thusis minutely divided by the air and mingled with the same to an explosivecharge. The said charge ejects through the opening 12 the gases ofcombustion resulting from the preceding working stroke, and is thencompressed and ignited by a sparking plug 13, effecting the next workingstroke of the piston.

The air valve A is so arranged, that the tension of its spring may beadjusted. By the said adjustment the length of the period, during whichthe vacuiuu in the crank chainber and the channel. 5, 7 is so great,that fuel. is sucked into the part 7 of the channel, and thus thequantity of fuel for the next charge is adjusted. The disk 11 causes theair current to strike the fuel spread on the bottom of the channel, sothat the air more forcibly carries with itself the said fuel andminutely divides the same. Besides by shifting the disk 11 the quantityof air passing through the channel is controlled. Consequently, thecharge of the cylinder may be adapted to the varying load of the engineor to a varying number of revolutions. The size of the cross section ofthe channel, however, may be so carefully adapted, that slidab-le,through slot in the Wall of the channel may be substituted for the disk11.

YVze claim:

1. In an internal combustion engine having a two-stroke cycle system, achannel eX- tending from the crank chamber to the cylinder, a miningchamber forming part of the channel, having a substantially plane andhorizontal bottom portion, van'iple Width and slight height, a means forspreading fuel on the bottom portion, the chamber therefore operating asan effective surface carburetor.

2. In an internal combustion engine of the two stroke cycle system,having a channel extending from the crank chamber to the cylinder and aninlet for the fuel leading to the said channel, .a mixing chamberformingpart of the channel and having a substantially plane andsubstantially horizontal bottom and further a great Width, the chamberthus operating as surface carburetor in association with a throttlebaffle member located, in the said channel and directing the air,passing from the crank chamber toward the fuel spread on the bottom ofthe mixing chamber.

In Witness whereof, We have hereunto signed our names.

OSKAR VSVENSSON. GUSTAF SVENSS'ON.

